I like that the bunker is limited in the amount that it can hold but I feel that the amount is too small and thus makes it a virtually useless building. Right now with it maxed out at level 12 you can only store 100k unit power which for larger players that have 1 million + unit power is absolutely useless. It ends up being maybe a hundred higher tier troops out of the thousands of total troops they have.
I suggest that one of 2 options be implemented:
Option 1, increase the power limit by 10x for each level. This would make a level 2 bunker hold 150k power limit instead of 15k and a level 12 bunker would hold 1,000,000 troop power.
Option 2, decrease the limit by 10x and change it to the number of units it could hold. This would mean that a level 2 bunker would hold 1500 units total of any type and at level 12 it would hold 10k units total.
I feel that either of these would still keep the game balanced but also allow people to defend a usable number of troops to use later.